Flow meter alarm device

ABSTRACT

A flow meter alarm device easily attached to and removed from a flow meter at various locations along the length of the flow meter. The device is compatible with flow meters which have a float for measuring flow velocity. The device preferably has two housings, extending from a third housing having a display surface, that define an area for receiving a flow meter. The extending housings are preferably drawn together by a threaded member thereby clamping the device onto the flow meter. A sensor mounted on the device, preferably an optical emitter coupled with an optical receiver, is able to detect the float. When the float is detected, a signal is produced by the device notifying that the flow rate has fallen outside a desired range. The device is adjustable to function with flow meters of various different dimensions.

FIELD OF INVENTION

[0001] The present invention relates to flow meters. More particularly,the present invention relates to a novel device easily attached to andremoved from a flow meter for signaling when flow rates reach a selectedvalue.

BACKGROUND

[0002] Conventional flow meters typically utilize a float membermoveable along the flow meter housing. Such movement may or may not beguided by a float rod. In either case, the float moves to a positionrepresentative of flow rate.

[0003] In general, the flow rate is determined by visual inspectionwithout automated systems for signaling when flow rate falls outside adesired range.

[0004] It is desirable to provide a device easily attached to andremoved from a flow meter to signal changes in flow rate, especiallycritical changes, and further to have a device which may accommodateflow meters of different sizes.

SUMMARY

[0005] The present invention provides a device designed to be easilymounted upon and removed from a flow meter, without disturbing the flowmeter as installed, to signal when flow rates reach a given readingand/or fall outside of a desired range. Spacer members, designed formounting on the device, enable use of the device with a number of flowmeters of different sizes.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The present invention will be understood from a consideration ofthe drawings wherein like elements are designated by like numerals and,wherein:

[0007]FIGS. 1, 2 and 3 respectively show front, side, and top views of adevice embodying the principles of the present invention in combinationwith a flow meter.

[0008]FIG. 4 is a sectional view of the device of FIG. 1, omitting theflow meter, looking in the direction of arrows 4-4.

[0009]FIG. 5 is an isometric view of the device of FIG. 1 in combinationwith a first and second spacer block.

[0010]FIG. 5a is an isometric view of the second spacer block.

[0011]FIG. 6 is a top view of the device of FIG. 1 in combination withthe first and second spacer blocks to accommodate a flow meter havingouter dimensions which differ from the flow meter of FIGS. 1-3.

[0012]FIG. 7 is an isometric view of the device of FIG. 1, showing thebeams directed by the emitters to their associated receivers.

[0013]FIG. 8 is a flow diagram showing the two operating sequences ofthe device of FIG. 1.

[0014]FIG. 9 is a top view of an alternative embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] To facilitate an understanding of the present invention, theinvention will be described with reference to a rotameter or variablearea type flow meter. However, those of skill in the art will realizethat the device embodying the teachings of the present invention isusable with any type of flow measuring device that utilizes a float.

[0016] Making reference to FIGS. 1-3, a flow meter 10 is shown thereincomprising a hollow, rectangular-shaped outer flow meter body 12 formedof a material having at least a transparent portion enabling viewing ofthe float 14. The float 14 is free to travel along the length of theflow meter. Flow meter 10 is adapted to be connected with a flow sourcevia inlet 12 a and outlet 12 b. Fluid flow rate through the flow meter10 is measured by means of float 14 which moves toward outlet 12 b asflow velocity increases, the flow rate being determined by graduationsprovided along the rotameter housing.

[0017] In a preferred embodiment, the device 20 comprises housingassembly 22 which includes a first housing 22 a, a second housing 22 b,and a third housing 22 c. Housings 22 a and 22 b are drawn toward oneanother to secure the device 20 to flow meter housing 12 by means of aclamping force. The clamping force is provided by screw 24 whichthreadedly engages a tapped opening 26 b in a clamping pin 26 extendingthrough third housing member 22 c. The head 26 a of pin 26 rests on acircular shoulder 31 a in member 31, while the circular flange 24 a ofscrew 24 rests against the outer surface of member 33, to draw the firsthousing 22 a and second housing 22 b toward each other thereby securelyattaching device 20 to flow meter housing 12. Loosening screw 24 allowsthe device to be easily removed and/or re-positioned along the length offlow meter housing 12. Screw 24, in the preferred embodiment is athumbscrew, although any similar threaded fastener could be used. As analternative embodiment, referring to FIG. 9, a spring 124, incombination with a pin 131 extending through housings 22 a-22 c, exertsa force on housings 22 a and 22 b to draw the first and second housingstogether thereby eliminating the need for a screw. As anotheralternative embodiment, the first and second housings (22 a,22 b) couldremain fixed, and the device frictionally secured by a threaded memberthreadedly engaging a tapped opening located on one of the first orsecond housings, one end of the threaded member making direct contactwith flow meter housing 12. The threaded member may be provided with arubber or rubber-like end cap to prevent the flow meter housing frombeing damaged and to enhance the frictional engagement.

[0018] Making reference to FIGS. 4-6, in applications where the device20 is intended for use with a flow meter having smaller dimensions thanthat shown in FIGS. 1-3, spacer blocks 28 and 30 are respectivelyattached to covers 32 and 34 each of which forms part of the housings 22b,22 a. Projections 28 a and 30 a provided on spacer blocks 28 and 30are sized to mate with openings in their associated covers, such asopening 32 a in cover 32, to provide an aligned snap fit therebetween.Device 20′, fitted with spacer blocks may be attached to a flow meter10′, functionally similar to flow meter 10 but having a width W₁ smallerthan the width W of flow meter 10. Ledges 30 b and 28 b also assist inproperly aligning the sensors of device 20′ with the path of movement offloat 14′ of the flow meter 10′. Screw 24 is tightened to provide aclamping force to secure device 20′ onto flow meter 10′ in the samemanner as described above with respect to flow meter 10. Clearanceapertures such as the apertures 30 c in the spacer blocks 28 and 30provide for the passage of light from emitters 40, 40′ to receivers 44,44′. Similar clearance apertures 35,36 are provided in covers 32 and 34,which are also aligned with the emitter and receiver. Spacer blocks ofdifferent dimensions can be used to accommodate flow meters of differentdimensions. As an alternative embodiment, spacer blocks could beattached to housings 22 a and 22 b via T-shaped slots in the housingswhich cooperate with mating T-shaped protrusions on the spacer blocks.

[0019] Other flow meters having widths only slightly different from thewidth of the first flow meter can be accommodated by the device withoutuse of the spacer blocks. The screw 24, in cooperation with the clampingpin 26, allows for some variation in flow meter width.

[0020] As an alternative embodiment, housing 22 c and pin 26 may be madeshorter and screw 24 may be lengthened to provide greater adjustmentrange in width. This would provide a greater range of travel of thehousing 22 a relative to housing 22 b, allowing the device to be affixedto different sized flow meters without the use of spacer blocks. Itshould further be noted that the spacer blocks, in addition toaccommodating flow meters of differing widths, also provide foralignment of the emitter and receiver with the float 14, by way of theledges, such as the ledges 30 b shown in FIGS. 5 and 5a.

[0021] Making reference to FIGS. 1, 4, and 7, housing 22 a, comprised ofcovers 33 and 34, contains optical emitters 40, 40′ mounted on a circuitboard 42. Optical emitters 40,40′ cooperate with optical receivers44,44′ and a microprocessor 47, mounted on circuit board 46, provided inhousing 22 b comprised of covers 31 and 32. Emitters 40,40′ respectivelydirect light to receivers 44,44′. Cover 34 protects the optical emittersand associated circuitry and provides a surface to interface with theflow meter housing 12 or a spacer block 28. Similarly, cover 32 protectsthe optical receivers and provides a second surface to interface withthe flow meter housing 12 or second spacer block 30. Apertures 35 and 36in covers 32 and 34 (together with clearance apertures in the spacerblocks) respectively allow the transmission of light between theemitters 40,40′ and receivers 44,44′. Alternatively, the opticalemitters may be located in the housing 22 b and the optical receiverslocated in housing 22 a. Alternatively, the emitters and receivers maybe located in the same housing 22 a or 22 b and employ a reflectivetechnique to detect the presence of float 14. Further, those skilled inthe art will recognize that other types of sensors including magnetic,inductive, capacitive, and ultrasonic may be used to detect the presenceof the float 14. Depending on the type of sensor used, the sensor andassociated electronics may be housed in housing 22 c with housings 22 aand 22 b serving as purely structural elements.

[0022] A signal line 50 inscribed on a transparent sight window 48provided in housing 22 c indicates the position where float 14 willenter the light beam emitted by the optical emitters 40,40′ and directedto the optical receivers 44,44′. The transparent window also enablesgraduations and/or numeric legends on the flow meter to be easilyviewed. Signal line 50 enables the user to accurately position thedevice 20 at a desired location along flow meter housing 12. The emitter40, receiver 44, and sight window 48, in one embodiment, are displacedfrom a center line (note line 4-4 of FIG. 1) and are preferably locatednear edge 64 on housing 22 c. This enables two devices to be mounted asclose as possible to one another enabling the threshold settingsrepresented by the sensing lines to be positioned as close as possiblewhen two devices are being used on the same flow meter.

[0023] A second device 20″ shown in dotted fashion in FIG. 1, may bemounted upon flow meter 10 with its edge 64″ facing edge 64 of the firstdevice 20. Using this orientation the devices 20 and 20″ and especiallythe sensing lines, may be positioned close to one another.

[0024] Power is supplied to device 20 from a suitable source (not shown)and logic is outputted from device 20 to a remote data collection device(not shown) via the power and logic connector 52. In the preferredembodiment, power and logic connector 52 extends from one end of housing22 b remote from the housing 22 c. If desired, the power and logicconnector 52 can extend from housing 22 a or from housing 22 c. In stillanother embodiment, a battery may be provided in the device 20 to supplypower and the logic (binary) output function can be omitted or providedvia wireless means.

[0025] Making reference to FIGS. 1, 4, 6, and 7, display 56 is comprisedof a red LED and a green LED arranged behind a translucent window andlocated on the housing 22 c adjacent to the transparent window. Whenpower is supplied to the device, the green LED is illuminated and thedevice is operational in a latching mode. In latching mode, when thefloat enters the beam created by emitter 40, an audible alarm 58 locatedon circuit board 42 sounds, the red LED is illuminated, and the logicoutput changes state i.e. one binary state for normal, opposite binarystate for abnormal. The logic (binary) output is conveyed through thepower and logic connector 52 and may be coupled to various types of datacollection and computer systems recognized and well known by thoseskilled in the art. The device returns to normal operation only afterthe reset button 62, extending outwardly from housing 22 b, is manuallypressed to reset device 20. Note that the second emitter 40′ andreceiver 44′are not required for the device to operate in latching mode.

[0026] By pressing and holding the reset button 62 for a given intervalwhen power is applied to device 20, the device operates in auto-resetmode. In auto-reset mode, the device utilizes both emitters 40,40′ andreceivers 44, 44′ to determine both the float location and its directionof movement by way of an internal program provided in microprocessor 47,coupled to receivers 44,44′. Emitter 40 and emitter 40′ are positionedin close proximity to each other such that float 14 is able to enterupper beam UB and lower beam LB substantially simultaneously. Beams UBand LB are represented by broken center lines extending between theirrespective emitter and receiver. It should be noted that the sensingline 50 is substantially parallel to the beam LB, for example, tofacilitate adjustment of the device 20 along the flow meter 10. Inauto-reset mode, when the float enters the lower beam LB created byemitter 40, the audible alarm 58 sounds, the red LED is illuminated, andthe logic output changes state. If float 14 continues to move upwardinto the beam UB and is displaced from beam LB, the logic output remainsunchanged and the audible alarm continues. If float 14 moves downwardand is initially displaced from beam UB and thereafter leaves beam LB,the internal program in the microprocessor 47 determines that float 14moved below beam UB, thereby turning off the audible alarm and providinga logic output indicating normal operation, responsive thereto.Thereafter, the green and red LEDs will flash until the reset button 62is pressed.

[0027] A variety of different procedures could be used for returning thedevice to normal operation after the float is sensed, such as employinga timer so no user intervention is required. Also, other methods ofsignaling that the float has been sensed, such as a wireless radiotransmission, are readily recognized by those skilled in the art. Thoseskilled in the art will further recognize that the reset button 62, theLED display 56, and the audible alarm 58 could be located on the housing22 c, or alternatively, on any other suitable location on the device.

What is claimed is:
 1. A device, for use with flow meters of a typehaving a movable float that indicates a rate of flow through the flowmeter, and having a given width between two opposing sidewalls andmeasured in a direction transverse to a path of movement of the float,comprising: a housing assembly including at least one sensor thatprovides an output when the float is in close proximity to the sensor,the housing assembly also including opposing first and second housings,connected by a third housing, defining a recess having a width at leastas large as said given width enabling the device to be releasablyattached to a flow meter without disconnecting the flow meter from afluid inlet or fluid outlet; means for apply a force to at least one ofthe opposing first and second housings to releasably secure the deviceto a flow meter; and, a signal generator in said housing assemblyproviding a signal responsive to said sensor output.
 2. The deviceaccording to claim 1, wherein said sensor comprises a firstemitter/receiver combination including a first emitter and a firstreceiver which cooperates with the first receiver to detect the float.3. The device according to claim 2, wherein said sensor furthercomprises a second emitter/receiver combination including a secondemitter and a second receiver which cooperates with the firstemitter/receiver combination to detect a direction of movement of thefloat.
 4. The device according to claim 2, wherein said first emitterand first receiver are of optical design.
 5. The device according toclaim 1, wherein said means for applying load includes a threaded memberwhich threadedly engages a tapped opening in the first housing, thethreaded member having an end making direct contact with the flow meterto secure the device to the flow meter.
 6. The device according to claim1, wherein said means for applying a force includes a spring whichapplies force to the opposing first and second housings to draw thefirst and second housings together.
 7. The device according to claim 1,wherein said means for applying a force includes a threaded membercooperating with a tapped member in said housing assembly to draw theopposing first and second housings together.
 8. The device according toclaim 1, including means for reducing the width of the recess toaccommodate flow meters having different widths.
 9. The device accordingto claim 1, wherein said recess enables the device to be selectivelypositioned along a path of the float.
 10. The device according to claim9, wherein the housing assembly further includes a viewing windowprovided with a signal line to facilitate alignment of the device alongthe path of the float.
 11. The device according to claim 1, wherein thesignal is an audible alarm.
 12. The device according to claim 1, whereinthe signal is a light.
 13. The device according to claim 1, wherein thesignal is a logic output.
 14. A device for use with various flow meters,each having a different width and each having a float that indicates arate of flow through the flow meter, each said width being measured in adirection transverse to a path of movement of said float, the devicecomprising: a housing assembly including at least one sensor thatgenerates an output when the float is in close proximity to the sensor,the housing assembly also including opposing first and second housings,a third housing connected between said first and second housings to forma substantially U-shaped configuration and defining a recess, a width ofthe recess being adjustable to enable the device to embrace flow metersof varying width; and, a signal generator responsive to said sensoroutput to provide an alarm condition.
 15. The device according to claim14, wherein said sensor comprises a first emitter and a first receiverwhich cooperates with the emitter.
 16. The device according to claim 15,wherein said sensor further comprises a second emitter and a secondreceiver which cooperates with the second emitter, and wherein the firstand second emitters and receivers cooperate to detect a direction ofmovement of the float.
 17. The device according to claim 15, whereinsaid first emitter and first receiver are of optical design.
 18. Thedevice according to claim 14, wherein said housing assembly furtherincludes means for releasably securing the device to a flow meterembraced by said device.
 19. The device according to claim 14, whereinthe first and second housings are releasably secured to the flow meterby a clamping device, comprising a threaded member which operates todraw the first and second housings together.
 20. The device according toclaim 14, wherein said housing assembly further includes a threadedmember for drawing the opposing first and second housings together toadjust the width of the recess and secure the device to a flow meter.21. The device according to claim 14, further comprising at least onespacer block connected to the device and positioned between the opposingfirst and second housings to adjust the width of the recess and securethe device to a flow meter.
 22. The device according to claim 21,wherein said spacer block includes protrusions, and wherein the firstand second housings include apertures which receive the protrusions toalign and secure the at least one spacer block to the device.
 23. Thedevice according to claim 21, wherein said spacer block includes atleast one ledge to align the device on the flow meter with the path ofthe float such that the at least one sensor is positioned to accuratelydetect the float.
 24. The device according to claim 15, wherein saidrecess is designed to enable the device to be slidably mounted andremoved without the need to disassemble the device.
 25. The deviceaccording to claim 24, wherein said housing assembly further includes atransparent window having a signal line that facilitates alignment ofthe device along the path of the float.
 26. The device according toclaim 25, wherein said signal line is substantially parallel to animaginary center line extending between the emitter and the receiver.27. The device according to claim 26, wherein the signal line is offsetfrom a center line of the device and is positioned closer to one edge ofthe housing.
 28. The device according to claim 14, wherein the signal isan audible alarm.
 29. The device according to claim 14, wherein thesignal is a light.
 30. The device according to claim 14, wherein thesignal is a logic output.
 31. A combination flow meter and device unit,comprising: a flow meter having a movable float that indicates a rate offlow through the flow meter, the flow meter also having a given widthmeasured in a direction transverse to a path of movement of the floatand being respectively connected to a fluid inlet and a fluid outlet;and, a device having a housing assembly including at least one sensorthat provides an output when the float is in close proximity to thesensor, the housing assembly also including opposing first and secondhousings, connected by a third housing, defining a recess, having awidth at least as large as the width of the flow meter, that enables thedevice to be easily attached to and removed from the flow meter withoutdisconnecting the flow meter from the fluid inlet or fluid outlet, thedevice further having means for applying a force to the opposing firstand second housings to releasably secure the device to the flow meter.32. The combination unit according to claim 31, wherein said sensorcomprises a first emitter/receiver combination including a first emitterand a first receiver which cooperates with the first receiver to detectthe float.
 33. The combination unit according to claim 32, wherein saidsensor further comprises a second emitter/receiver combination includinga second emitter and a second receiver which cooperates with the secondemitter to detect the float, and wherein the second emitter/receivercombination cooperates with the first emitter/receiver combination todetect a direction of movement of the float.
 34. The combination unitaccording to claim 31, wherein said means for applying a force includesa threaded member which threadedly engages a tapped opening in one ofsaid first and second housings, the threaded member contacting asidewall of the flow meter to secure the device to the flow meter. 35.The combination unit according to claim 31, wherein said means forapplying a force includes a spring which applies force to the opposingfirst and second housings to draw the first and second housingstogether.
 36. The combination unit according to claim 31, wherein saidmeans for applying a force includes a threaded member cooperating with atapped member in said housing assembly to draw the opposing first andsecond housings toward one another.
 37. The combination unit accordingto claim 31, further comprising at least one spacer block, positionedbetween the opposing first and second housings, for adjusting a width ofthe recess.
 38. The combination unit according to claim 37, wherein saidspacer block includes protrusions, and wherein the first and secondhousings include apertures which receive the protrusions to align andsecure the at least one spacer block to the device.
 39. The combinationunit according to claim 38, wherein said spacer block includes at leastone ledge to properly position the flow meter within said recess toalign the at least one sensor with the path of the float such that theat least one sensor is positioned to detect the float.
 40. Thecombination unit according to claim 31, wherein said recess enables thedevice to be slideably moved in directions aligned with and transverseto a length of the flow meter.
 41. The combination unit according toclaim 31, wherein said housing assembly further includes a viewingwindow provided with a signal line that facilitates alignment of thedevice along the length of the flow meter.
 42. The combination unitaccording to claim 31, wherein the signal is an audible alarm.
 43. Thecombination unit according to claim 31, wherein the signal is a light.44. The combination unit according to claim 31, wherein the signal is alogic output.
 45. An alarm device for use with flow meters, comprising:a substantially U-shaped housing assembly composed of first and secondhousings each joined near one end to a third housing forming theU-shaped configuration; a sensor mounted in one of said first and secondhousings for sensing a movable member in a flow meter to provide analarm condition; opposing surfaces of said first and second housingspositioned to embrace opposing sidewalls of a flow meter, said opposingsurfaces having shapes conforming to a shape of the flow meter opposingsidewalls enabling the device to be slidable along said opposingsidewalls in first and second directions transverse to one another; and,means for releasably clamping the device to a flow meter by exerting aclamping force only on said opposing sidewalls.
 46. The alarm deviceaccording to claim 45, further comprising a plurality of spacers ofdiffering thickness and each designed to be releasably joined to atleast one of said opposing surfaces to accommodate flow meters ofdiffering widths measured between said opposing sidewalls.
 47. A methodof providing a signal responsive to a rate of flow as indicated by aflow meter of a type having a movable float, the flow meter having agiven width between two opposing sidewalls measured in a directiontransverse to a path of movement of the float, the method comprising:placing a housing assembly on the flow meter, the housing assemblyincluding at least one sensor that provides an output when the float isin close proximity to the sensor, the housing assembly also includingopposing first and second housings, connected by a third housing,defining a recess having a width at least as large as said given width,enabling the housing assembly to receive the flow meter within therecess and to be releasably attached to the flow meter withoutdisconnecting the flow meter from a fluid inlet or a fluid output;applying a force to at least one of the opposing first and secondhousings to releasably secure the device to a flow meter; and generatinga signal responsive to said sensor output.
 48. The method of claim 47,wherein the generating step generates at least one of an audio and avisual signal.
 49. The method of claim 47, wherein the step of applyinga force includes the step of turning a threaded member cooperating witha tapped member in said housing assembly to draw the opposing first andsecond housings together.
 50. The method of claim 47, wherein the stepof placing the housing assembly includes the step of aligning the devicealong a path of the float using a viewing window located on the housingassembly.
 51. The method of claim 47, wherein the step of placing thehousing assembly includes the step of inserting at least one spacerblock between the opposing first and second housings to reduce the widthof the recess to accommodate a flow meter of reduced size.
 52. A methodof providing a signal responsive to a rate of flow as indicated by aflow meter of a type having a movable float, the flow meter having agiven width between two opposing sidewalls measured in a directiontransverse to a path of movement of the float, the method comprising:placing housings of first and second sensing devices on the flow meter,each housing including at least one sensor that provides an output whenthe float is in close proximity to the sensor, each housing having arecess for receiving the flow meter, and releasably securing the firstand second sensing devices to the flow meter; and slideably moving thehousings along the flow meter to provide signals for different flowrates.
 53. The method of claim 52, wherein the step of slideably movingthe housings includes the step of providing viewing windows, located oneach of the housings and substantially aligned with respective beamscreated by their associated sensors, to facilitate alignment of each ofthe devices along the path of the float.
 54. The method of claim 53,further comprising providing each viewing window with a signal linedisplaced from a longitudinal central axis of its associated housing sothat the signal line is closer to one edge of its associated housing andfurther away from an opposite edge of its associated housing, andmounting the housings upon the flow meter in orientations to enable theviewing windows to be positioned closer to one another than in anotherorientation.
 55. The method of claim 53, wherein providing each viewingwindow further comprises providing each viewing window to be of a sizesufficient to view graduations and indicia on the flow meter to furtherfacilitate alignment of each device at a desired location along the flowmeter.